cdesktopenv/cde/programs/dtinfo/DtMmdb/diskhash/disk_hash.h

143 lines
4.3 KiB
C++

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these libraries and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/*
* $XConsortium: disk_hash.h /main/3 1996/06/11 17:16:15 cde-hal $
*
* Copyright (c) 1993 HAL Computer Systems International, Ltd.
* All rights reserved. Unpublished -- rights reserved under
* the Copyright Laws of the United States. USE OF A COPYRIGHT
* NOTICE IS PRECAUTIONARY ONLY AND DOES NOT IMPLY PUBLICATION
* OR DISCLOSURE.
*
* THIS SOFTWARE CONTAINS CONFIDENTIAL INFORMATION AND TRADE
* SECRETS OF HAL COMPUTER SYSTEMS INTERNATIONAL, LTD. USE,
* DISCLOSURE, OR REPRODUCTION IS PROHIBITED WITHOUT THE
* PRIOR EXPRESS WRITTEN PERMISSION OF HAL COMPUTER SYSTEMS
* INTERNATIONAL, LTD.
*
* RESTRICTED RIGHTS LEGEND
* Use, duplication, or disclosure by the Government is subject
* to the restrictions as set forth in subparagraph (c)(l)(ii)
* of the Rights in Technical Data and Computer Software clause
* at DFARS 252.227-7013.
*
* HAL COMPUTER SYSTEMS INTERNATIONAL, LTD.
* 1315 Dell Avenue
* Campbell, CA 95008
*
*/
#ifndef _disk_hash_h
#define _disk_hash_h
#include "diskhash/bucket_array.h"
#include "diskhash/disk_bucket.h"
#include "dstr/void_ptr_array.h"
#include "dstr/index_agent.h"
#include "storage/page_storage.h"
#define COLLISION_BIT 0x2
extern int steps[];
extern int no_steps;
class disk_hash : public index_agent
{
public:
disk_hash(page_storage* key_oid_store,
int prime = 32801,
int expected_n = 100
);
// prime and expected
// key set size
virtual ~disk_hash();
Boolean insert(data_t& v); // insert a key
Boolean remove(data_t& v); // remove a key
Boolean member(data_t& v); // member test
void clean(); // remove all keys
//int no_keys() const { return n; }; // return key set size
// WARNING: -1 is the terminate condition!!!
int first_bucket();
disk_bucket* get_bucket(int&);
void next_bucket(int&);
// output this with print_f handling the printing of whole data_t.
// pointer to data_t as void* is passed to print_f
ostream& asciiOut(ostream& out, print_func_ptr_t print_f);
ostream& asciiOut(ostream& out);
istream& asciiIn(istream& in);
protected:
void init_params(int prime, int expected_n);
void sync_params();
void set_M(unsigned int newM) { M = newM; };
void set_v(unsigned int newv) { v = newv; };
void set_k(unsigned int newk) { k = newk; };
void set_p(unsigned int newp) { p = newp; };
void set_n(unsigned int newn) { n = newn; };
Boolean rehash(data_t& w); // rehash all keys in buckets + w
Boolean _rehash(fstream& pool); // rehash keys from pool
Boolean _insert(data_t& v, Boolean rehash_if_fail);
Boolean member(data_t& v, disk_bucket*& b, int& slot_num) const;
void caching(disk_bucket& b, data_t& w, int slot_num);
void out_params();
protected:
unsigned int M; // number buckets
unsigned int v; // number of overflow buckets
unsigned int k; // parameter used in the 1st level hash function
unsigned int p; // prime number p
unsigned int n; // current key set size
bucket_array* bucket_vector; // bucket array
void_ptr_array* hash_vector; // hash array
void_ptr_array* k_vector; // k param array
void_ptr_array* r_vector; // r param array
page_storage* key_store; // key_recordOID store
buffer& buf;
pm_random rand_generator; // rand generator
};
#endif